1. Field of the Invention
This invention relates to conveyor belts, and, more particularly, to scraper blades for cleaning conveyor belts.
2. Related Art
Conveyor belts are often used to convey materials that adhere to the surface of the belt. In order to maintain efficient operation of the conveyor belt system, the excess debris must be removed from the surface of the belt. Accordingly, there are various types of scraper blade assemblies that are used to scrap the debris from a surface of a conveyor belt.
A common type of scraper blade assembly comprises a plurality of mounted scraper blades extending across the transverse axis of the conveyor belt. The blade assemblies are mounted on support arms which are fixed to and extend from a transverse rotatable support shaft. Rotation of the transverse support shaft moves the scraper blades into and out of contact with the conveyor belt. Applying a torque to the support shaft increases the contacting force of the scraper blades against the belt.
During installation and use of the standard scraper blade assemblies, the support shaft is torqued and locked in position when a predetermined contacting force is exerted on the belt by the scraper blade assemblies. As the scraper blades wear down, the contacting force on the belt steadily decreases, thereby reducing the cleaning efficiency of the scraper blade assembly. Over the useful life of the scraper blades, the support shaft must be adjusted several times to compensate for wear on the blades. After prolonged use, standard clamps and set screws become ineffective to maintain and adjust the contacting force. A further problem with this method is that it is not possible to adjust a single scraper blade, i.e., an adjustment to one is an adjustment to all because it is the shaft on which the scraper blades are mounted that is adjusted. A still further problem is that the scraper blades undergo significant stress from vibrations resulting from the fact that the blades are only bolted or screwed directly on to the face of the assembly.
Therefore, there is a need for a conveyor belt scraper blade assembly having a blade that is vertically adjustable within the assembly such that the blade is vertically adjustable in relation to the conveyor belt and the housing for the blade. There is further a need for a means for easily and efficiently removing a blade from the scraper blade assembly so that a worn blade can be replaced with a new blade.
In addition to the above, conventional blade assemblies do not provide any means for loosening or diluting debris on a conveyor belt prior to scraping the conveyor belt with a blade assembly. Therefore, there is a need for a conveyor belt scraper blade assembly that loosens and dilutes the debris, such as by spraying water on the surface of the conveyor belt, prior to scraping the conveyor belt surface with a blade assembly.